it.larusba.integration.couchbase.document.transformer.RemoteNeo4jTransformer.java Source code

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Here is the source code for it.larusba.integration.couchbase.document.transformer.RemoteNeo4jTransformer.java

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/**
 * Copyright (c) 2016 LARUS Business Automation [http://www.larus-ba.it]
 * <p>
 * This file is part of the "LARUS Integration Framework for Neo4j".
 * <p>
 * The "LARUS Integration Framework for Neo4j" is licensed
 * under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package it.larusba.integration.couchbase.document.transformer;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

import javax.ws.rs.core.MediaType;

import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPut;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.HttpClientBuilder;
import org.json.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import it.larusba.integration.common.document.bean.JsonDocument;

/**
 * {@link DocumentTransformer} a REST call to a Neo4j Server Extension which is
 * responsible for the conversion of a JSON string to a Cypher statement
 * 
 * @author Mauro Roiter
 */
public class RemoteNeo4jTransformer implements DocumentTransformer<String> {

    private static Logger LOGGER = LoggerFactory.getLogger(RemoteNeo4jTransformer.class);

    private InputStream inputStream;

    @Override
    public String transform(String documentKey, String documentType, String jsonDocument) {

        String returnMessage = "JSON successfully transformed";

        try {

            transformJson2Cypher(documentKey, documentType, jsonDocument);
        } catch (IOException e) {

            returnMessage = "Error during JSON transformation";
            LOGGER.error("Error during JSON transformation: " + e.getMessage());
        }

        return returnMessage;
    }

    /**
     * It perform the REST call to the URL configured in the
     * transofrmer.properties file
     * 
     * @throws IOException
     */
    private void transformJson2Cypher(String documentKey, String documentType, String jsonDocument)
            throws IOException {

        Properties prop = new Properties();
        String propFileName = "transformer.properties";

        inputStream = getClass().getClassLoader().getResourceAsStream(propFileName);

        if (inputStream != null) {
            prop.load(inputStream);
        } else {
            throw new FileNotFoundException("property file '" + propFileName + "' not found in the classpath");
        }

        // get the URL property value
        String urlJson2Cypher = prop.getProperty("transformer.url");

        JsonDocument documentToTransform = new JsonDocument(documentKey, jsonDocument, documentType);

        HttpClient httpClient = HttpClientBuilder.create().build();

        HttpPut putRequest = new HttpPut(urlJson2Cypher);
        putRequest.addHeader("content-type", MediaType.APPLICATION_JSON);

        JSONObject json = new JSONObject(documentToTransform);

        StringEntity entity = new StringEntity(json.toString());

        putRequest.setEntity(entity);

        HttpResponse response = httpClient.execute(putRequest);

        if (response.getStatusLine().getStatusCode() != 200) {

            throw new RuntimeException("Failed : HTTP error code : " + response.getStatusLine().getStatusCode());
        }
    }
}